Digital subscriber line (DSL) communication is primarily directed to using existing telephone lines, known as the local loop, between the telephone company's central office and the customer premises to enable data communications. A series of digital subscriber line standards variations have been issued including asymmetric digital subscriber line (ADSL) and very-high-data-rate digital subscriber line (VDSL). Later digital subscriber line standards generally aim at increasing data throughput rates. The rate at which data can be transmitted through the local loop depends in part on the length of the local loop, the presence of any circuit conditioning circuits such as bridge taps in the local loop, diurnal environmental variations, and other conditions or factors.
Communications circuits may be combined in one or more integrated circuits to achieve desirable price points for consumer electronics. Several communications components including filters, amplifiers, encoders, decoders, signal processing components, error correction components, and memory may be combined or integrated in a single integrated circuit or chip. Specialized chips and/or chip sets may be developed by semiconductor manufacturers to support specific communication protocols. As new communication standards or variations of standards are released, new chips and/or chips sets are designed and released for sale.